1. Field of the Invention
This invention relates to chains having a center link in the form of a loop, such as rivetless type chain and bar loop type chain. More specifically, the invention is directed to an anti-collapsing chain having a loop center link.
2. Description of the Prior Art
Chains having a center link in the form of a loop, such as a rivetless type chain and bar loop type chain, are used in trolley conveyor systems, long conveyors where chain weight must be considered such as retarding and assembly conveyors, flight conveyors operating in materials that would tend to pack and fully enclose chain joints, and drag conveyors. A major problem encountered with chain having loop center links is that the chain links can collapse during service. The chain is normally operated over a series of sprockets or wheels for the purpose of power transmission. Under normal operating conditions, the chain is taut and subject to a tensile load. Certain operating conditions, such as overrunning loads and excessive chain accumulation on the slack strand side, enable the chain links to collapse or move together in overlapping relationship. When this happens, particularly with rivetless type chain, the links can become disassembled rendering the chain inoperable. It is desirable to maintain an open chain joint in conveyors operating in abrasive or corrosive materials that would tend to pack in fully enclosed joints. A jet of water can be directed toward the drive sprockets, and thus, flush out the open joints as the chain passes over the sprocket. It is desirable to provide an economical interlock, to prevent open joint chain from collapsing and providing the opportunity for the chain to become disassembled.